860
FXUS64 KOHX 220049
AFDOHX

Area Forecast Discussion
National Weather Service Nashville TN
649 PM CST Fri Nov 21 2025

...New MESOSCALE UPDATE...

.KEY MESSAGES...
Updated at 640 PM CST Fri Nov 21 2025

- Periods of showers and scattered thunderstorms through early
  Saturday morning. A couple of strong thunderstorms cannot be
  ruled out Friday night.

- Another high chance for showers and thunderstorms Monday night
  through Tuesday.

- Mild temperatures lasting into early next week, then turning
  sharply colder by Thanksgiving.

&&

.MESOSCALE UPDATE FOR 00Z SOUNDING...
Issued at 640 PM CST Fri Nov 21 2025

The data from our 00Z sounding are in and there are several items
worth discussing. First, the weather balloon launch took place
during a light shower, so there is some rain contamination to
consider. Still, the Precipitable Water is 1.49", which is a
record high value for this date. The mean value is 0.56", so this
gives us a PWAT+ value of 266, meaning that the observed PWAT is
266% of the daily mean value. Given the absence of any meaningful
dry layer, it`s going to be difficult (but certainly not
impossible) for any storm to become severe. There is a modicum of
instability present in the pre-frontal environment. The SBCAPE is
87 J/kg and we did manage to squeak out a -1 Lifted Index. The
700-500 mb lapse rate is 6.1C/km, which is about what one might
expect in an environment with such a climatologically high PWAT.
We do expect instability parameters to increase along and near
the cold frontal boundary later on tonight, so there is that to
consider. Finally, there is a good amount of low-level wind shear
present. The 0-3 km Storm Relative Helicity is 192, with both
speed and directional shear being present. Overall, this does not
change our messaging. There is a low risk of severe storms later
this evening and overnight, with straight-line winds being the
primary threat, and a very low chance of a tornado.

&&

.SHORT TERM...
(Rest of today through Saturday)
Issued at 1016 AM CST Fri Nov 21 2025

Morning showers are exiting the Plateau with only a few lingering
showers remaining across Middle TN. Cloud cover has been pretty
consistent through the morning, but webcams show some breaks
starting to develop across the SW as we see increased mixing. As
mentioned in the previous update, SPC does have our CWA under a
marginal risk (level 1 of 5) for severe weather today. That said,
the environment is very conditional at this time. If cloud cover
manages to break out even more and provide some additional surface
heating, the environment will be better for a few strong storms
this evening. For now, the message remains the same, there
remains a low chance for one or two strong storms through the
evening and again late tonight ahead of the approaching cold front.
Taking a look at latest forecast soundings, not much change.
Still seeing weak CAPE and poor mid- level lapse rates. That said,
there is strong low- level shear today which is the reason for
the low risk for a few storms to become severe.

Saturday the cold front moves through pushing most of the showers
and thunderstorms out of the area. There will be a low chance for
some lingering post frontal showers Saturday afternoon, but
mostly dry weather is expected for folks.

&&

.LONG TERM...
(Saturday Night through next Friday)
Issued at 1016 AM CST Fri Nov 21 2025

Dry weather sticks around for the weekend before another front
brings showers and thunderstorms across Middle TN Monday and
Tuesday. This set up will be very similar to Thursday/Friday as an
area low pressure passes to our NW. This will bring about another
1-2 inches of rain. As before, not seeing much of a severe weather
threat with weak CAPE and mid-level lapse rates. At this time, the
main cold front looks to pass through Tuesday afternoon. This will
bring some breezy conditions with gusts to 20-25 mph through the
morning and afternoon. Mostly dry and cold weather then develops
through the rest of the week going into the Thanksgiving holiday.

Tuesday night temperatures drop into the low 40s across the NW and
mid to upper 40s elsewhere. By Wednesday night, temperatures drop
a bit more, into the upper 20s to low 30s. Through the remainder
of the week, overnight lows will drop into the 20s and 30s. For
now, the coldest night looks to be Friday with temperatures
possibly dropping into the mid 20s.

&&

.AVIATION...
(00Z TAFS)
Issued at 508 PM CST Fri Nov 21 2025

Patches of light rain and low ceilings are impacting Middle
Tennessee as we head into the evening. A cold front is poised to
sweep through the mid state later tonight, which will further
erode ceilings and visibilities. However, the HRRR is not too keen
on our storm potential, and the NBM hourly TS probabilities are in
the single digits throughout the night. So we`ve included
TEMPO/PROB30 groups for anticipated shower activity, but am not
yet confident enough in our TS potential to include in the TAFs
at present. Ceilings will be slow to improve during the day
tomorrow as the upper trough lags behind the surface front.

&&

.PRELIMINARY POINT TEMPS/POPS...
Nashville      60  70  45  65 /  60  10   0   0
Clarksville    57  65  40  64 /  60  10   0   0
Crossville     57  66  41  61 /  70  30   0   0
Columbia       61  72  43  66 /  50  10   0   0
Cookeville     59  67  42  62 /  70  30   0   0
Jamestown      57  65  41  60 /  80  30  10   0
Lawrenceburg   61  72  44  65 /  50  10   0   0
Murfreesboro   60  71  43  65 /  60  10   0   0
Waverly        57  66  42  65 /  50  10   0   0

&&

.OHX WATCHES/WARNINGS/ADVISORIES...
None.
&&

$$

SHORT TERM...Cravens
LONG TERM....Cravens
AVIATION.....Rose